All emergency services are on Sjursøya in Oslo after an evacuation alarm was triggered inside a tunnel in Kongshavnveien.
According to the police, the alarm has gone off from the tunnel system connected to the Follo line.
Four workers have so far been evacuated, while two to four workers have not been accounted for. The cause of the incident is not known so far.
The fire brigade is on its way into the tunnel to find the cause, as well as the people who have not been accounted for, the police wrote on Twitter.
Source: © NTB Scanpix / #Norway Today / #NorwayTodayNews
Do you have a news tip for Norway Today? We want to hear it. Get in touch at firstname.lastname@example.org